Former Pussycat Dolls star Ashley Roberts has axed two upcoming gigs in the U.K.

The singer, who is promoting her upcoming debut solo album Butterfly Effect, had been due to perform on a string of dates of the touring Summer Live event, but she has since pulled out of dates in Manchester and Sheffield on 17 and 18 July (14), respectively.

She has not given a reason for the cancellations, but has assured fans she will still be playing in Liverpool on 20 July (14).

In a series of posts on her Twitter.com page on Monday (20Jun14), she writes, "Hi peeps, I'm devastated to say that due to unforeseen circumstances, I'm no longer going to be @ (the Manchester or Sheffield legs of) SummerLive. So sorry...

"I'm still going to be bringing the love to @EchoArena for... Summer Live in Liverpool though...sorry again".